Although ketamine inhibits ATP-sensitive K (K(ATP)) channels in rat ventricular myocytes and abolishes the cardioprotective effect of ischemic preconditioning in isolated rat hearts and in rabbits in in vivo, no studies to date specifically address the precise mechanism of this prevention of ischemic preconditioning by ketamine. This study investigated the mechanism of the blockade of ischemic ...

The idea of preconditioning is usually associated with solution techniques for solving linear systems or eigenvalue problems. It refers to a general method by which the original system is transformed into one which admits the same solution but which is easier to solve. Following this principle we consider in this paper techniques for preconditioning the matrix exponential operator, e A y 0 , us...

We propose efficient preconditioning algorithms for an eigenvalue problem arising in quantum physics, namely the computation of a few interior eigenvalues and their associated eigenvectors for the largest sparse real and symmetric indefinite matrices of the Anderson model of localization. We compare the Lanczos algorithm in the 1987 implementation by Cullum and Willoughby with the shift-and-inv...

The preconditioned conjugate gradient (CG) method is becoming accepted as a powerful tool for solving the linear systems of equations resulting from the application of the finite element method. Applications of the non-linear algorithm are mainly confined to the diagonally scaled CG. In this study the coupling of preconditioning techniques with non-linear versions of the conjugate gradient and ...

Multiplicative preconditioning is a popular tool for handling linear systems of equations provided the relevant information about the associated singular values is available. We propose using additive preconditioners, which are readily available for both general and structured ill conditioned input matrices and which preserve matrix structure. We introduce primal and dual additive preconditioni...

We present two minimum residual methods for solving sequences of shifted linear systems, the right-preconditioned shifted GMRES and shifted Recycled GMRES algorithms which use a seed projection strategy often employed to solve multiple related problems. These methods are compatible with general preconditioning of all systems, and when restricted to right preconditioning, require no extra applic...

To determine which preconditioning and pretensioning techniques should be applied to soft tissue grafts during anterior cruciate ligament (ACL) reconstruction to avoid loss of tension after surgery, fresh semitendinosus and tibialis anterior tendons underwent tensile mechanical testing with 4 pretensioning and/or preconditioning techniques. A mechanical tester was used to collect the data. Grou...

By combining our weakly randomized preconditioning with aggregation and other known and novel techniques, we facilitate the solution of a homogeneous linear system of equations. We demonstrate the power of this approach and show some extensions.

We apply our recent preconditioning techniques to the solution of linear systems of equations and computing determinants. We combine these techniques with the Sherman–Morrison–Woodbury formula, its new variations, aggregation, iterative refinement, and advanced algorithms that rapidly compute sums and products either error-free or with the desired high accuracy. Our theoretical and experimental...

By combining our weakly randomized preconditioning with aggregation and other known and novel techniques, we facilitate the solution of a homogeneous linear system of equations. We demonstrate the power of this approach and show some extensions.